Alkylacrylate ester composition for anchoring materials in or to concrete or masonry

ABSTRACT

This invention provides a composition for anchoring materials in or to concrete or masonry. The composition comprises an alkylacrylate ester monomer, an alkylacrylate ester/methacrylic acid copolymer, a free-radical catalyst and a filler.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No.08/487,870, filed Jun. 7, 1995, issued as U.S. Pat. No. 5,643,994 onJul. 1, 1997.

TECHNICAL FIELD

This invention relates to a composition for anchoring materials in or toconcrete or masonry. More particularly, this invention relates to aalkylacrylate ester/methacrylic acid copolymer composition for anchoringmaterials in or to concrete or masonry.

BACKGROUND OF THE INVENTION

Many applications require that a material be anchored in or to concreteor masonry. For example, anchor bolts are employed in various fields ofengineering as strengthening or reinforcing members in rock formations,or concrete or masonry structural bodies. The bolts, which are typicallymetallic, are inserted into holes in the rock formations, or concrete ormasonry structural bodies, and are fixed or anchored therein by means ofan anchor composition. Typically, the anchor composition cures orhardens (polymerizes) to form a strong bond between the rock formation,or the concrete or masonry structural body and the bolt. In concrete andmasonry, anchor bolts are used for reinforcement. Anchor bolts are alsoused for attaching objects to concrete or masonry. Objects that havebeen attached to concrete or masonry using anchor bolts include, but arenot limited to, electrical conduits, panels, piping and wall sections.Adhesive anchors are preferred over mechanical anchors for anchoring insoft concrete or masonry because adhesive anchors place less stress onthe concrete or masonry. As used herein, the term "masonry" shallinclude, but is not limited to, stone, brick, ceramic tile, cement tile,hollow concrete block and solid concrete block.

A useful anchor composition should be inexpensive, provide for a strongbond between the concrete or masonry and the material to be anchored tothe concrete or masonry, be easy to dispense at the location of use andhave a long storage shelf life. Some anchor compositions that have beenused include compositions based on aromatic vinyl esters, aromaticpolyesters and epoxies. These compositions can be expensive or may notprovide the desired bond strength between the concrete or masonry andthe material that is anchored in or to the concrete or masonry.

An example of the anchor compositions of the prior art is found inJapanese Patent Application Sho59-122762 ("JP '762"). Generally, JP '762discloses an anchor composition comprising a monomer, a polymer solublein the monomer, aggregate and a hardening agent. With respect to themonomer component, JP '762 discloses a broad range of compounds whichinclude methacrylate esters. With respect to the polymer component, JP'762 discloses a similarly broad range of compounds which includesmethacrylate esters and acrylic acid, and further discloses the use ofcopolymers. Moreover, JP '762 discloses a composition comprising 70 to95% by weight of the monomer and 5 to 30% by weight of the polymer.

Notably, however, JP '762 fails to recognize the unexpected andsurprising properties of fast cure time and pull out strength realizedby the selection of a methacrylate ester monomer and a copolymer of amethacrylic ester and methacrylic acid in the formation of an anchorcomposition as shown herein. The unexpected and surprising resultsachieved by this particular combination is shown in certain of theexamples set forth below in which significantly shorter cure times andgreater pull out strengths are exhibited by the compositions of thepresent invention as compared to other compositions which fall withinthe scope of the broad disclosure of JP '762. As a result, thecomposition of the present invention represent a novel and unobviousadvancement over the prior art.

SUMMARY OF THE INVENTION

The present invention provides a composition for anchoring materials inor to concrete or masonry that comprises from about 20% to about 90% byweight of the entire composition of a alkylacrylate ester monomer and analkylacrylate ester/methacrylic acid copolymer; a free-radical catalyst;and a filler.

In a preferred embodiment, the present invention provides a compositionfor anchoring materials in or to concrete or masonry that is made bymixing a first composition and a second composition. The firstcomposition comprises from about 20% to about 90% by weight of theentire composition of a methacrylate ester monomer and methacrylateester/methacrylic acid copolymer; and a filler. The second compositioncomprises a free-radical catalyst.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides an anchor composition for anchoringmaterials in or to concrete or masonry. The materials to be anchored inor to concrete or masonry include, but are not limited to, metallicobjects, such as steel bolts, ceramics, other concrete or masonryobjects, plastics, glasses and woods.

The composition comprises an alkylacrylate ester monomer, a analkylacrylate ester/methacrylic acid copolymer, a free-radical catalystand a filler. It may also be desirable to include in the composition athixotropic agent, a chain transfer agent, a free-radical inhibitor, afragrance, an activator, a promoter and/or a pigment. It is alsorecognized that other components known to those skilled in the art maybe included in the composition. Such components may include, but are notlimited to, antifoaming agents, wetting agents, fungicides, impactmodifiers, crosslinking agents and coupling agents.

The composition may be dispensed using various methods known to thoseskilled in the art. For example, the composition may be dispensed usinga dual cartridge device similar to a caulk gun, or the composition maybe dispensed using a glass or film capsule. The composition may also bedispensed in bulk from bulk containers using meter-mix equipment, whichis known to those skilled in the art. U.S. Pat. Nos. 4,651,875,4,706,806 and 4,729,696, the disclosures of which are herebyincorporated by reference, are directed to glass capsules. It isrecognized that the amounts of the various components of the anchorcomposition may vary depending on the type of dispensing system used. Inpreferred dispensing methods, the anchor composition is formed by themixing of a first composition and a second composition. Typically, themixing occurs immediately before the anchor composition is to be used.For example, when the anchor composition is dispensed using a dispensinggun, the first composition and the second composition, which arecontained in separate cartridges of the dispensing gun, may be mixed asthey are ejected from the cartridges and applied to either the concreteor masonry, the material to be anchored to the concrete or masonry orboth. Similarly, when the anchor composition is dispensed using a glasscapsule, the capsule is typically comprised of two chambers that containthe first composition and the second composition respectively. When theglass capsule is crushed, the two chambers are crushed and the contentsare allowed to mix, forming the anchor composition. Last, when theanchor composition is dispersed in bulk, a first composition and asecond composition may be stored in separate bulk containers andcombined through pumping with mixing in the appropriate ratio to makethe anchor composition.

The anchor composition preferably contains a methacrylate ester monomerand a methacrylate ester/methacrylic acid copolymer. It is preferable ifthe methacrylate ester/methacrylic acid copolymer has a weight-averagemolecular weight in the range of about 10,000 to about 60,000. Morepreferably, the copolymer has weight-average molecular weight in therange of about 20,000 to about 40,000.

In general, the methacrylate ester/methacrylic acid copolymer is solublein the methacrylate ester monomer to form a solution. The ratio ofcopolymer to monomer is in the range of about 1 to 9 to about 2.5 to 1by weight. Preferably, the copolymer to monomer ratio is in the range ofabout 1 to 4 to about 1 to 1.5 by weight. More preferably, the copolymerto monomer ratio is in the range of about 1 to 4 to about 1 to 2.5 byweight.

As used herein, the phrase "methacrylate ester monomer" shall meanesters of methacrylic acid, including, but not limited to, the methyl,ethyl, propyl, isopropyl, butyl, tert-butyl, cyclohexyl, 2-ethylhexyland tetrahydrofurfuryl esters of methacrylic acid. As used herein thephrase "methacrylate ester/methacrylic acid copolymer" shall mean acopolymer which can theoretically be made from methacrylate ester andmethacrylic acid monomers.

The copolymer may be a random, block, graft or alternating copolymer.The polymer also can be linear or branched and can be based on two ormore different methacrylate ester monomers. It is also contemplated thatthe methacrylate ester monomer component may be a mixture of differentmethacrylate monomers, and the methacrylate ester/methacrylic acidcopolymer component may be a mixture of more than one copolymer.

Generally, the monomer/copolymer combination is present in the anchoringcomposition in the range of about 20% to about 90% by weight of theentire composition. Preferably, the monomer/copolymer combination ispresent in the anchoring composition is an amount in the range of about20% to about 60%. More preferably, the monomer/copolymer combination isabout 40% to about 45% by weight of the entire composition when thecomposition is dispensed using a dispensing gun, and about 20% to about30% by weight of the entire composition when the composition isdispensed using a glass capsule.

The anchor composition also comprises a free-radical catalyst, whichstarts the free-radical polymerization of the methacrylate ester andmethacrylic acid monomers in the composition, which results in ahardened or cured composition. Examples of free-radical catalystsinclude, but are not limited to, peroxides, such as the diacylperoxides, hydroperoxides, peresters, peracids and radiant energy orthermal energy, i.e. ultraviolet light and heat. Examples of specificfree-radical catalysts include, but are not limited to, dibenzoylperoxide, cumene hydroperoxide, tertiary butyl peroxide, dicumylperoxide, tertiary butyl peroxide acetate, tertiary butyl perbenzoateand ditertiary butyl azodiisobutyronitrile. Examples of the diacylperoxides include, but are not limited to, dibenzoyl peroxide, succinicacid peroxide, dilauroyl peroxide, didecanoyl peroxide and diisononanoylperoxide. The most preferred free-radical catalyst is dibenzoylperoxide. It is also contemplated that more than one free-radicalcatalyst may be used in the composition. The free-radical catalyst isusually present in the composition in the range from about 0.5% to about10% by weight of the entire composition. Preferably, the catalyst isfound in the composition in the range of about 1% to about 5% by weightof the entire composition. Even more preferably, the free-radicalcatalyst is about 2% by weight of the entire composition.

The composition can also include a catalyst activator (also called aninitiator). Throughout this application, the terms "activator" and"initiator" are used interchangeably. Representative activators includean aldehyde-amine condensation product, organic sulfonyl chlorides,tertiary amines or mixtures thereof. For example, such a condensationproduct can be made from butyraldehyde and a primary amine, such anamine being, for example, aniline or butylamine. Also suitable asactivators are tertiary amines such as N,N-dimethyl aniline,N,N-dimethyl toluidine, N,N-diethylaniline, N,N-diethyl toluidine,N,N-bis(2-hydroxyethyl)-p-toluidine, N,N-bis(hydroxypropyl)-p-toluidineand the like. A preferred activator isN,N-bis(2-hydroxyethyl)-p-toluidine.

The composition can also include a promoter, which is an organic salt ofa transition metal such as cobalt, nickel, manganese or ironnaphthenate, copper octoate, copper acetylacetonate, iron hexoate oriron propionate.

In concrete anchoring, much of the heat of polymerization is lost to themass of concrete. Therefore, activators such asN,N-bis(2-hydroxyethyl)-p-toluidine may be used to achieve the desiredrapid cure times. However, when anchoring in hollow concrete blocks,portions of the anchor composition may not contact the concrete, andheat loss to the surroundings is minimized, which can result inincomplete curing of the bulk anchor composition. In such cases, it maybe preferable to add a chain transfer agent to the composition. Chaintransfer agents are discussed below. The amount of activator and chaintransfer agent that gives acceptable cure speeds, shelf life and bulkcure properties for a particular application and composition can bedetermined by those skilled in the art by routine optimization.

The initiators and activators, if part of the composition, can be addedin an amount up to about 10% by weight of the entire composition.Preferred amounts are in the range of about 0.01 to about 1.5%.Promoters are typically used in amounts up to about 0.5% by weight ofthe composition, and preferably about 1 part per million to about 0.5%by weight of the entire composition.

The anchor composition may also comprise a thixotropic agent. Athixotropic agent that is added to a composition causes the compositionto become more fluid, i.e. less viscous, when agitated, stirred or mixedor otherwise subjected to such shear forces. It is useful to include athixotropic agent in the anchor composition to insure that thecomposition has the desired viscosity during application and after thecomposition is applied. In addition, a thixotropic agent may be added toan anchor composition to prevent the settling of other solid componentsof the composition and to increase the viscosity of the composition. Thethixotropic agent also facilitates dispensing of the composition becausewhen a shear force is applied, e.g. expulsion of the composition from adispensing gun, the thixotropic agent makes the resulting compositionless viscous, and therefore, more easy to expel from the cartridges ofthe dispensing gun. The thixotropic agent may be found in the anchorcomposition in an amount in the range of 0.5% to about 10% by weight ofthe entire composition. Preferably, the thixotropic agent is found inthe composition in an amount in the range of about 2% to about 7% byweight of the entire composition. Most preferably, the thixotropic agentis about 5% when the composition is dispensed from a dispensing gun.Typically, no thixotropic agent is needed when the anchor composition isdispensed using a glass capsule. An example of a suitable preferredthixotropic agent is fumed silica. Also contemplated are the varioussilicas made by the various methods known in the art, includingpyrolysis of silicon tetrachloride and precipitation. Other suitablethixotropic agents include the various organoclays and various fibers.In some anchor compositions, the thixotropic agent may also beconsidered a filler. A suitable silica thixotropic agent is Aerosil®R202, which may be obtained from the Degussa Corporation of RidgefieldPark, N.J. It is also contemplated that more than one thixotropic agentmay be used in the anchor composition.

The anchor composition of the present invention also comprises one ormore fillers. Fillers are typically added to compositions for variousreasons, including to reduce shrinkage of the composition that may occurduring polymerization and to reduce the cost of the composition, asfillers replace a portion of the more expensive components of the anchorcomposition. The filler may also provide for improved bond strength ofthe anchor composition when polymerized and help to prevent the settlingout of other particulate materials in the composition. Generally, thefiller is an inert, inorganic, solid, particulate compound. By inert itis meant that the filler does not detrimentally interact with any othercomponent of the composition. Examples of suitable fillers include, butare not limited to, crushed glass, glass beads, quartz, silica,limestone, alumina, various clays, diatomaceous earth and othermaterials such as mica, flint powder, kryolite, alumina trihydrate,talc, sand, pyrophyllite, blanc fixe, granulated polymers such aspolyethylene, hollow glass and polymer beads, zinc oxide, novaculite,calcium sulfate and mixtures thereof. Preferred fillers are quartz,glass and silica. Fillers may be treated with coupling agents to improvebonding to the polymer matrix. Examples of coupling agents which may beused to treat the fillers are silanes, titanates and zirconates.

Generally, fillers can be found in the composition in an amount in therange of 10% to about 90% by weight of the composition. In certainpreferred embodiments in which the anchor composition is dispensed bymeans of a dispensing gun, fillers are found in the range of about 20 toabout 80% by weight of the composition, and more preferably, about 40 toabout 65% by weight of the composition. In certain preferred embodimentsin which the anchor composition is dispensed by means of a glasscapsule, fillers, including the glass or film capsule, are found in therange of about 40 to about 90% by weight of the composition, and morepreferably, about 65 to about 80% by weight of the composition.

The exact particle size of the filler will depend on the desiredconsistency of the composition and the method for dispensing the anchorcomposition. For example, fillers having a large average particle size(300 microns and larger) may clog static mixers that are used indispensing systems such as dispensing guns. On the other hand, fillershaving a large particle size can be used in glass capsules. Preferredparticle sizes are about 50 microns or larger. However, in cases where afiller is used to prevent the settling out of other particulate matterin a composition, a particle size smaller than 50 microns may bedesired. It is also recognized that a filler having a particle size lessthan 50 microns may be used in combination with other fillers, somehaving particle sizes greater than 50 microns.

Preferred fillers for use in anchor compositions that are to bedispensed using a dispensing gun have average particle sizes in therange of about 50 to about 275 microns, and even more preferably in therange of about 150 to 200 microns. Preferred fillers for use in anchorcompositions that are to be dispensed using a glass capsule have averageparticles sizes in the range of about 100 to about 3,000 microns, andeven more preferably in the range of about 1200 to 2000 microns.

The anchor composition may also include a free-radical chain transferagent. Free-radical chain transfer agents are included in anchorcompositions to facilitate polymerization. Chain transfer agents alsohave the effect of limiting the molecular weight of the polymers thatare formed by the polymerization. The use of a free-radical chaintransfer agent provides for an acceptable polymerization speed and formore complete polymerization of the anchor composition, particularlywhen a large mass of the composition is to be polymerized. Preferredfree-radical chain transfer agents include mercaptans such as dodecylmercaptan. In addition, other chain transfer agents are known to thoseskilled in the art, and a suitable free-radical chain transfer agent maybe readily selected by those skilled in the art. In certain preferredembodiments in which the anchor composition is dispensed by means of adispensing gun, the free-radical chain transfer agent may be found inthe range of about 0 to about 4% by weight of the composition, and morepreferably, about 0.1 to about 2% by weight of the composition. Incertain preferred embodiments in which the anchor composition isdispensed by means of a glass capsule, the free-radical chain transferagent may be found in the range of about 0 to about 5% by weight of themonomer/polymer composition, and more preferably, about 0.5 to about 4%by weight of the monomer/polymer composition.

The anchor composition may also include a free-radical inhibitor. Afree-radical inhibitor is added to the composition to inhibit thepolymerization of monomers in the composition until such polymerizationis desired. The addition of a free-radical inhibitor also increases thestorage shelf life of the anchor composition. In certain preferredembodiments in which the anchor composition is dispensed by means of adispensing gun, the free-radical inhibitor may be found in the range ofabout 0 to about 0.1% by weight of the composition, and more preferably,about 0.005 to about 0.05% by weight of the composition. In certainpreferred embodiments in which the anchor composition is dispensed bymeans of a glass capsule, the free-radical inhibitor may be found in therange of about 0 to about 0.16% by weight of the monomer/polymercomposition, and more preferably, about 0.02 to about 0.08% by weight ofthe monomer/polymer composition.

In one embodiment of the present invention, the anchor composition isformed by mixing a first composition and a second composition. The firstcomposition contains the polymerizable monomers and may contain aninhibitor to prevent polymerization of the monomers until desired, andthe second composition contains a free-radical catalyst. When the firstcomposition and the second composition are combined, polymerizationoccurs. Free-radical inhibitors are known to those skilled in the art. Apreferred free-radical inhibitor is trimethyl hydroquinone. Othersuitable free-radical inhibitors include, but are not limited to,hydroquinone, hydroquinone monomethyl ether, t-butyl catechol andnaphthaquinone. It is also contemplated that more than one free radicalinhibitor may be employed in the anchor composition.

The anchor composition may also contain a fragrance. A fragrance is usedin an anchoring composition to mask any odor of the composition that isthought undesirable or unpleasant. A preferred fragrance is AtlantaFragrance 16332. Similarly, a pigment may be employed to color theanchoring composition. Suitable pigments are known to those skilled inthe art.

In a preferred embodiment the anchor adhesive is made by mixing a firstcomposition and a second composition. The first composition comprises amethacrylate ester monomer, a methacrylate ester/methacrylic acidcopolymer and a filler. The first composition may also comprise athixotropic agent, a chain transfer agent, a free-radical inhibitor, afragrance, an activator, a promoter and/or a pigment. The secondcomposition contains a free-radical catalyst. The second composition mayalso include a filler, a thixotropic agent, a fragrance, and/or apigment. It is also contemplated that both the first composition and thesecond composition may contain some of the same components.

The ratio of the first composition to the second composition may be inthe range of 1 to 1 to about 40 to 1. Preferably, the ratio of the firstcomposition to the second composition is about 10 to 1.

Also provided is a method for anchoring a material in or to concrete ormasonry that comprises the steps of delivering the above-describedanchor composition to concrete or masonry, the material to be anchoredto the concrete or masonry or both; contacting the material to beanchored, the concrete or masonry and the anchor composition; andpolymerizing the anchor composition.

The delivery of the anchor composition may be accomplished by any methodknown to those skilled in the art, including by cartridge in adispensing gun, by glass capsules or from bulk containers throughmeter-mix equipment. The composition is applied to either the concreteor masonry, the material to be anchored in or to the concrete ormasonry, or both. Then, the concrete or masonry and the material to beanchored to the concrete or masonry are contacted so that both theconcrete or masonry and the material to be anchored comes into contactwith the anchor composition. The anchor composition is then polymerized.

The following examples are provided to illustrate particular embodimentsof the invention and are not intended to limit the scope of theinvention or the claims in any manner.

EXAMPLES Experimental Protocols Preparation of Anchor Compositions to beDispensed From a Cartridge Using a Dispensing Gun

The appropriate amounts of polymer and monomer are weighed. The monomeris added to a container and the polymer is slowly added, with mixing toobtain a polymer in monomer solution. It is preferred to mix the monomerand polymer solution using a dispenser, and then to further mix thesolution on a jar mill at 3-5 rpm for between 24-48 hours.

To an appropriate amount of the above monomer/polymer solution is addedinhibitor, activator, chain transfer agent, fragrance and otheringredients. The composition is mixed, preferably using a dispenser.Next, the thixotropic agent is added with shear mixing followed byaddition of the filler. If more than one filler is to be included in theanchor composition, it is preferable to add the first filler, then mix,then add the second filler and so on until the desired number of fillershave been added to the composition. To make a two component composition,each component may be made separately according to the above-describedprocedure.

Preparation of Anchor Compositions to be Dispensed From a Glass Capsule

The appropriate amounts of polymer and monomer are weighed. The monomeris added to a container and the polymer is slowly added, with mixing. Itis preferred if the monomer and polymer solution are mixed using adisperser and then further mixed on a jar mill at 3-5 rpm for between24-48 hours. Inhibitor and activator are added, with mixing, as desired.

The free-radical catalyst, typically a peroxide, is introduced into asmall glass tube (inner tube), which is then sealed. The sealed smallglass tube is placed into a large glass tube (outer tube) that has beensealed at one end. The above-described polymer/monomer solution and anyfiller is added to the large glass tube and the large glass tube issealed.

Pull Out Performance

Medium Weight Concrete Block

A medium weight concrete block that was approximately 4"×8"×16", whichwas free of surface moisture was used. Typically, five replicate pullout tests were run for each adhesive composition tested.

First, three equally spaced 65 mm deep holes were drilled in the 8"×16"side of the concrete block. Then, the holes were cleaned with a brush,with compressed air and a vacuum. An adhesive composition was injectedinto the drilled holes, and a 1/4"-20 threads per inch×5" stainlesssteel rod type 304 is inserted into the adhesive-containing hole with atwisting motion. The time before pull out testing (also called curetime) was in the range of about 0.5 hours to about 72 hours. Thestainless steel rod was then connected to an Instron universal tester,Model TTC, Instron Corporation, Canton, Mass., and the rods were pulledat 0.2"/minute until failure. The maximum load and failure type was thenrecorded. Preferably, in an acceptable anchor composition, the pull outperformance is about 2200 pounds or greater in concrete block. Mostpreferably, the material that has been anchored to the concrete ormasonry, or the concert or masonry itself fails before the adhesivecomposition.

Medium Weight Hollow Concrete Block

A 6"×8"×16" (1" wall thickness) medium weight hollow concrete block,free of surface dampness, was drilled with two 16 mm holes on the 8"×16side of the block (four total). The holes were cleaned of dust, and 16mm polyethylene screens were installed in the holes. The adhesivecomposition is injected into the screen to fill the screen, and a 10 mmrod is inserted into the adhesive in the screen with a twisting motion.The adhesive was allowed to cure, typically for 24 hours. The rod wasthen pulled on a universal tester at 0.2"/min. until failure of theadhesive, rod or concrete. (16 mm polyethylene screens and 10 mm rodsmay be obtained from SPIT, Valence, France.)

5.000 psi Compressive Strength Concrete

A 3'×6'×12" to 18" deep 4,000-5,000 psi concrete slab, which was curedat least 28 days, and which was free of surface moisture, was drilledwith holes. The holes were spaced in the concrete in accordance withASTM E488-90. The holes were cleaned, and adhesive was injected into theholes followed by the insertion of Grade 5 zinc plated rods with achrome seal. The adhesive was cured for a period, typically 2 to 24hours, and the rods were then pulled using a hydraulic jack untilfailure of the adhesive, rod or concrete.

Torque Performance

A hollow medium weight concrete block having dimensions 6"×8"×16" (1inch wall thickness), free of surface dampness, was drilled with 2 16 mmholes in each hollow cavity on the 8"×16" side of the block (fourtotal). The holes were cleaned and then a 16 mm polyethylene screen,which are known to those skilled in the art, was inserted into theholes. An adhesive composition was injected to fill the screens, and a10 mm rod was inserted into the screens containing the adhesive. Theadhesive was allowed to cure for a certain time and then a 1/4" thicksteel plate with a hole was placed over the rod. A washer was installedand a nut was hand tightened on the rod. The nut was torqued clockwisewith a socket wrench and torque transducer until failure of the rod,concrete or adhesive.

It should be noted that three types of concrete blocks that are known tothose skilled in the art have been used in the various examples setforth below: medium weight concrete block; 5,000 psi compressivestrength concrete; and medium weight hollow concrete block. Unlessspecified otherwise, "concrete block" or "concrete" shall mean mediumweight concrete block.

Materials

The following table shows materials, specific chemical compositions,trade names, suppliers and locations of the suppliers for the variousmaterials. This list is intended to be illustrative of various materialsand should not be construed as limiting the specification or the claimsin any manner.

    ______________________________________                                                           Trade                                                        Material Composition Name Supplier Location                                 ______________________________________                                        PMMA 2016                                                                             Methyl/n-  Elvacite ®                                                                          ICI     Wilmington,                                 butyl 2016 Acrylics DE                                                        methacrylate                                                                  Copolymer                                                                    PMMA 2008 Methyl Elvacite ® ICI Wilmington,                                methacrylate/ 2008 Acrylics DE                                                methacrylic                                                                   acid (2%)                                                                     copolymer                                                                    PMMA 2010 Polymethyl Elvacite ® ICI Wilmington,                            methacrylate 2010 Acrylics DE                                                PMMA 2021 Methyl Elvacite ® ICI Wilmington,                                methacrylate/ 2021 Acrylics DE                                                ethyl                                                                         acrylate (5%)                                                                 copolymer                                                                    MMA Methyl  ICI Wilmington,                                                   Monomer methacrylate  Acrylics DE                                             HET N,N-bis(2-  RSA Corp. Danbury, CT                                          hydroxyethyl)                                                               p-toluidine                                                                    Dodecyl   Aldrich Milwaukee,                                                  Mercaptan   Chemical WI                                                       Tamsil ™ 8 Silica Tamsil ™ 8 Unimin Elco, IL                             (2 micron)  Specialty                                                           Minerals                                                                   F55 Silica Sand  U.S. Ottawa, IL                                              Silica (ca. 200  Silica                                                       Sand microns)                                                                 ATH 00 Treated  Nyco Willsboro,                                               20774 alumina  Minerals NY                                                     Trihydrate  Inc.                                                              (8 micron)                                                                   Quartz Quartz 1/2   Agsco Wheeling,                                           1/2  (ca. 150  Corp. IL                                                        micron)                                                                      Huber SB- Alumina  Huber Norcross,                                            30-SP Trihydrate  Solem GA                                                     (ca. 50  Division                                                             micron)                                                                      ATH 21 Treated  Nyco Wilisboro,                                               20774 Alumina  Minerals NY                                                     Trihydrate (2  Inc.                                                           micron)                                                                      AFR 400 Di-benzoyl  ATOCHEM Buffalo, NY                                        peroxide in  North                                                            Plasticizer  America                                                          (40% BPO)                                                                    ANS Di-benzoyl  ATOCHEM Buffalo, NY                                            peroxide in  North                                                            Plasticizer  America                                                          (55% BPO)                                                                    CAB-O- Treated Fumed  Cabot Tuscola, IL                                       SIL ® M5 Silica  Corp.,                                                      Cab-O-Sil                                                                     Division                                                                   Aerosil ® Treated Fumed Aerosil ® Degussa Ridgefield                  R202 Silica R202  Park, NJ                                                    Fragrance   Atlanta Kennesaw,                                                16332   Fragrance GA                                                           TMHQ Trimethyl  Aldrich Milwaukee,                                             Hydroquinone  Chemical WI                                                    Cadox Dibenzoyl  Akzo Dobbs                                                   BFF 50 Peroxide  Chemicals Ferry, NY                                             Inc.                                                                       Quartz #4   Agsco Wheeling,                                                      Corp. IL                                                                 ______________________________________                                         BPO is dibenzoyl peroxide.                                               

Examples of Adhesive Compositions Example 1

    ______________________________________                                        First              % By Weight of                                               Composition* First Composition                                              ______________________________________                                        MMA monomer/MMA polymer                                                                          39.85                                                        solution                                                                      (20% Elvacite ® 2021 in                                                   MMA)                                                                          Quartz 1/2  53.4                                                              Dodecyl mercaptan 0.5                                                         Trimethyl hydroquinone 0.0161                                                 Silica (Aerosil ® R202) 5.4                                               N,N-bis (2- 0.5                                                               hydroxyethyl)-p-                                                              toluidine                                                                     Fragrance-16332 0.35                                                           % By Weight of                                                               Second Composition* Second Composition                                        Di-benzoyl peroxide 50                                                        (AFR 400-40% di-benzoyl                                                       peroxide)                                                                     Silica (Tamsil ™ 8) 30                                                     Quartz 1/2  20                                                              ______________________________________                                         *Pigments were added to both the first composition and the second             composition. The first composition contained about 0.02% American Colors      VC1000 white, and the second composition contained about 1% of American       Colors VC50457 rust. The abovedescribed anchor composition is preferably      dispensed by a dispensing gun or by bulk dispensation using metermix          equipment.                                                               

Example 2

    ______________________________________                                                                % By Weight of                                          Composition Composition                                                     ______________________________________                                        Large Glass Tube        22.10                                                   MMA monomer/MMA polymer                                                       solution (20% Elvacite ® 2021                                             in MMA)                                                                       N,N-bis(2-hydroxyethyl)-p- 0.67                                               toluidine                                                                     Quartz #4 41.78                                                               Small Glass Tube 1.37                                                         Di-benzoyl peroxide                                                           (Cadox BFF50)*                                                                Glass 34.08                                                                 ______________________________________                                    

The above-described anchor composition is preferably dispensed by aglass capsule. The glass is supplied by the small and large glass tubesthat hold the composition when the delivery system is crushed.

Example 3

    ______________________________________                                        First              % By Weight of                                               Composition First Composition                                               ______________________________________                                        Solution of MMA monomer and                                                                      43.289                                                       MMA/MAA copolymer                                                             (30% Elvacite ® 2008C in MMA)                                             Trimethyl Hydroquinone 0.016                                                  HET 0.518                                                                     Aerosil φ R202 4.123                                                      Agsco 100-140 silica sand 51.535                                              Dodecyl Mercaptan 0.518                                                        % By weight of                                                               Second Composition Second Composition                                         AFR 400 (40% BPO) 49.75                                                       Agsco Quartz 1/2  19.90                                                       Tamsil ™ 8 (silica) 29.85                                                  VC-80000 Black (iron oxide) 0.50                                            ______________________________________                                    

The first composition and the second composition were combined in aratio of 10:1 respectively. The above-described anchor composition ispreferably dispensed by a dispensing gun or by bulk dispensation usingmeter-mix equipment. After a 24 hour period of cure, the pull outperformance of the composition of Example 3 was measured at 3,832 lbs.

Example 4

    ______________________________________                                                          % By Weight of                                                Resin Solution Composition Composition                                      ______________________________________                                        MMA monomer       59.41                                                         MMA/MAA copolymer 34.89                                                       Trimethyl Hydroquinone 0.0377                                                 HET 3.77                                                                      Dodecyl Mercaptan 1.89                                                         % By Weight of                                                               Glass Capsule Composition Composition                                         Resin Solution Composition 22.17                                              Lucidol CH50 (50% BPO) 2.03                                                   Quartz sand (800 to 2000 33.39                                                microns)                                                                      Glass 42.42                                                                   (inside and outside vials)                                                  ______________________________________                                    

The above-described anchor composition is preferably dispensed by glasscapsules. The catalyst was placed into a vial and then sealed. Thesealed vial containing the catalyst was then placed into a larger secondvial together with the components of the resin solution composition andthe filler in accordance with the above weight percentages. The secondvial was then sealed.

Example 5

    ______________________________________                                        First          % By Weight of First                                             Composition Composition                                                     ______________________________________                                        PMMA 2021      9.0                                                              MMA Monomer 20.9                                                              HET 0.3                                                                       ATH 21 20774 29.9                                                             Quartz 39.9                                                                    % By Weight of Second                                                        Second Composition Composition                                                AFR 400 50                                                                    Quartz 1/2  20                                                                ATH 21 20774 30                                                             ______________________________________                                    

The first composition and the second composition were combined in aratio of 10:1 respectively. The pull out performance was measured inmedium weight concrete block. After a 72 hour period of cure, the pullout performance of the composition of Example 5 was measured at 2,830lbs.

Example 6

This example shows various compositions that may be used in practicingthe present invention.

    ______________________________________                                        Composition     1      2        3    4                                          Type of PMMA 2021 2008 2021 2021                                            ______________________________________                                        % Polymer in Monomer                                                                          10     55       30   20                                         % Polymer Solution 39.73 88.2 27.2 38.8                                       Filler-Quartz 1/2  53 10.3 36.3 51.8                                          Filler-Nyco ATH 21   36.3                                                     Thixotropic Agent 53 0.5  9.1                                                 Pull out in Concrete 2410 2200 2605 2510                                      Block (lbs)                                                                 ______________________________________                                    

The above compositions were injected into concrete block using adispensing gun containing a coaxial cartridge. In each composition, HETwas used as a catalyst activator (0.5 to 1.3%). Dodecyl mercaptan wasused as a chain transfer agent in compositions 1 and 2 (0.5%), andAerosil® R202 was used as a thixotropic agent, except for composition 4,which used Attagel 50. The compositions were dispensed in a ratio of 10parts of the above described compositions to 1 part activator. Theactivator comprised 50% AFR 400, 20% Quartz 1/2 and 30% Tamsil™ 8. Thepull out performance was measured in medium weight concrete block aftera cure time of between 24-72 hours. In general, a pull out performanceof 2200 lbs or greater in medium weight concrete block is required.

Comparative Examples Example 7

Table 1 below compares a commercially available anchor adhesive product,Ready Fix, which is based on aromatic polyesters, with commerciallyavailable structural adhesives based on acrylates having no inorganicparticulate filler.

                  TABLE 1                                                         ______________________________________                                        Composition    Pull Out (lbs)                                                 ______________________________________                                        Ready Fix      2160                                                             Plexus MA 300 400                                                             Plexus MA 310 850                                                             Plexus MA 320 260                                                           ______________________________________                                    

Ready Fix may be obtained from Red Head, Scotland. Plexus MA 300, PlexusMA 310 and Plexus MA 320 may be obtained from ITW Adhesive Systems,Danvers, Mass.

Table 1 shows that the pull out performance of the commerciallyavailable acrylate structural adhesives are below the pull outperformance acceptable for an anchor adhesive.

Example 8

Table 2 below shows the pull out performance of anchor compositionscontaining methyl methacrylate polymers of various weight averagemolecular weights. Each composition contained about 99.75% of a PMMA/MMAsolution. The compositions were mixed to a viscosity of approximately4000 to 10,000 centipoise. (Viscosities were measured on a Brookfieldviscometer using an HA6 spindle at 23° C.). Each solution also contained0.25% HET and 5% ANS (40% BPO). No fillers were used. Each of thecompositions were mixed by hand and injected into concrete block using adispensing gun containing a one component cartridge.

                  TABLE 2                                                         ______________________________________                                                PMMA      PMMA       PMMA    PMMA                                       Polymer 2016 2008 2010 2021                                                 ______________________________________                                        Polymer Methyl/n- Methyl-    Methyl- Methyl-                                    Type butyl metha- metha- metha-                                                metha- crylate/ crylate/ crylate/                                             crylate methacrylic ethyl ethyl                                               copolymer acid acrylate acrylate                                               copolymer copolymer copolymer                                               Polymer 60,000 36,000 84,000 118,000                                          Weight                                                                        Average                                                                       Molecular                                                                     Weight                                                                        Pull Out 1120 1250 1380 1700                                                  (lbs) -72                                                                     hr cure                                                                     ______________________________________                                    

The data show that, generally, as the molecular weight of the polymerincreases, the pull out strength also increases.

Example 9

Table 3 below shows the pull-out performance of anchor compositionscontaining various types and sizes of fillers. Each anchor compositioncontains a solution of PMMA/MMA mixed to have a viscosity of about 4000centipoise (viscosities were measured on a Brookfield viscometer usingan HA6 spindle at 10 rpm at 23° C.), 0.17-25% HET and 3-6% ANS (40%BPO). In addition, compositions 3 and 4 contain 0.6 to 1.0% CAB-O-SIL®M5.

                  TABLE 3                                                         ______________________________________                                                 PMMA    PMMA    PMMA  PMMA  PMMA  PMMA                                 Polymer 2016 2016 2016 2021 2021 2021                                       ______________________________________                                        %        67.0    49.9    59.3  39.6  33.1  29.9                                 PMMA/MMA                                                                      Solution                                                                      Filler 1 2 8 200 200 200 50                                                   Size                                                                          (microns)                                                                     Filler 1 32.8 49.9 39.5 59.6 66.6 39.9                                        wt %                                                                          Filler 2      8                                                               Size                                                                          (microns)                                                                     Filler 2      29.9                                                            wt %                                                                          Pull Out 1530 1620 2210 2580 2540 2600                                        (lbs) 72                                                                      hr. cure                                                                    ______________________________________                                    

Pull out was conducted using medium weight concrete blocks.

    ______________________________________                                        Size (microns)      Filler                                                    ______________________________________                                        2                   Tamsil ® 8                                              8 ATH 00 20774                                                                200 F55 Silica Sand                                                           50 Huber SB-30-SP                                                             150 Quartz 1/2                                                              ______________________________________                                    

Each of the compositions were mixed by hand and injected using adispensing gun containing a one component cartridge.

To achieve the desired pull out performance, the anchor composition ofthe present invention includes a filler, preferably an inorganic,insoluble, inert filler. Table 3 shows that the pull out strength of ananchor composition increases with increased particles size of thefiller.

Example 10

Pull Out Performance in 5,000 psi Compressive Strength Concrete

    ______________________________________                                                            Composition of                                              Ready Fix Example 1*                                                        ______________________________________                                        Pull Out (lbs) 5800     6000                                                    2 hr cure                                                                     Pull Out (lbs) 7100 7200                                                      24 hr cure                                                                  ______________________________________                                         *Compositions were the same as those of Example 1, except that no fraganc     was added.                                                               

Pull Out and Torque Performance in Hollow Concrete Blocks

    ______________________________________                                                             Composition of                                             C-Mix 3000 Example 1*                                                       ______________________________________                                        Pull Out (lbs) 1080      1310                                                   2 hr cure                                                                     Pull Out (lbs) 18.1 20.3                                                      24 hr cure                                                                  ______________________________________                                    

C-Mix 3000 is a commercially available aromatic polyester anchoradhesive, which can be obtained from SPIT, France.

The composition of Example 1 above was compared to commercial productsin 5,000 psi compressive strength concrete and in 55/8×75/8155/8 inchhollow concrete block. The performance of the composition of Example 1is equivalent or superior to commercial adhesives based on aromaticpolyesters and aromatic vinyl esters.

Example 11

The following example compares a commercially available anchor adhesivethat is delivered using a glass capsule with compositions of the presentinvention, which are delivered using a glass capsule. Each of anchorcomposition A and B comprised 21.9% PMMA/MMA solution, 41.3% quartz 4,0.88% HET, 1.8% Lucidol CH50 BPO and 33.7% glass (from the glasscapsule, which acts as a filler when crushed).

Table 4 below shows the pull out strengths of the various compositionsin 5,000 psi compressive strength concrete.

                  TABLE 4                                                         ______________________________________                                                 Hilti HEA   A       B                                                ______________________________________                                        Polymer                  2021    2008                                           % polymer in  20 30                                                           Solution                                                                      Dodecyl   0.43                                                                mercaptan (%)                                                                 Pull Out (lbs)- 16600 13130 16600                                             1 hour                                                                        Pull Out (lbs)- 16800 14530 16700                                             24 hour                                                                     ______________________________________                                    

Hilti HEA can be obtained from the Hilti Corporation, Tulsa, Okla.Lucidol CH50 can be obtained from ATOCHEM, Buffalo, N.Y.

Example 12

The following example compares two pairs of anchor adhesivecompositions. The first pair of anchor adhesive compositions contain amethacrylate ester/ethyl acrylate copolymer in concentrations of 20 and30% by weight of monomer solution. The second pair of anchor adhesivecompositions contain a methacrylate ester/methacrylic acid copolymeralso in concentrations of 20 and 30% by weight of monomer solution.Apart from the differences in copolymer composition and concentration,all of the anchor adhesives were composed of two compositions combinedin a 10 to 1 ratio. The first composition comprises about 43.3% byweight of monomer/copolymer solution, about 4.1% by weight Aerosil R202,0.016% by weight trimethyl hydroquinone, about 0.52% by weight dodecylmercaptan, about 0.052% by weight HET, and about 51.5% by weight 100-140silica sand. The second composition comprises about 49.8% by weight AFR400 (40% BPO), about 19.9% by weight Agsco quartz 1/2, about 29.9% byweight Tamsil™ 8, and about 0.5% by weight VC-80000 Black (iron oxide).

Table 5 below shows the pull out strengths of the various compositionsin medium weight concrete block after 0.5 hours of cure at 72° F. Table5 also shows the reaction exotherm data in maximum temperature and themaximum temperature achieved by the compositions at 72° F. Table 5further shows the pull out strengths of the various compositions whenmolded and tested in steel molds. This test, referred to herein as theconical mold pull test, provides a method of eliminating theexperimental variable associated with the conditions of the concreteblock. Table 6 shows the pull out strengths of the various compositionsin medium weight concrete block after one and two hours of cure at 20°F. These data demonstrate the superior cure times of the MMA/MAAcopolymer compositions as compared to the MMA/EA copolymer compositions.

                  TABLE 5                                                         ______________________________________                                                          Exotherm  Exotherm                                             Pull Test Test at Test at Conical                                             at 72° F. 72° F. 72° F. Mold Pulls                       1/2 hr. Time* temp** 72° F. 1 hr.                                     Composition cure (lbs) (sec) (°C.) cure (lbs)                        ______________________________________                                        20% 2008C                                                                             3810      540       103     6820                                        30% 2008C 3750 465 115 6550                                                   20% 2021C 3310 730 105 5490                                                   30% 2021C 3110 690 105 5710                                                 ______________________________________                                         *Time to maximum temperature                                                  **Maximum temperature                                                    

                  TABLE 6                                                         ______________________________________                                                    Pull Test at 20° F.                                                                 Pull Test at 20° F.                             Composition 1 hr. cure (lbs) 2 hr. cure (lbs)                               ______________________________________                                        20% 2008C   NC           3850                                                   30% 2008C 1410 3300                                                           20% 2021C NC 3440                                                             30% 2021C 1180 2590                                                         ______________________________________                                         NC  Not cured                                                            

What is claimed is:
 1. A low-temperature curable composition foranchoring materials in or to concrete or masonry, which compositioncomprises:a. alkylacrylate ester monomer; b. a copolymer ofalkylacrylate ester and methacrylic acid monomers; c. from about 10% toabout 90% by weight of an inert, inorganic, solid, particulate filler;d. from about 0.5% to about 10% by weight of a free-radical catalyst; e.from about 0.1% to about 5% by weight of a chain transfer agent; and f.from about 0.01 to about 10% by weight of an activator,wherein saidcomposition is curable at 20° F. (-7° C.).
 2. The composition of claim 1wherein the polymer to monomer ratio is in the range of about 1 to 9 toabout 2.5 to 1 by weight.
 3. The composition of claim 1 wherein thepolymer to monomer ratio is in the range of about 1 to 4 to about 1 to2.5 by weight.
 4. The composition of claim 1 wherein the combination ofmonomer and copolymer comprises about 20% to about 90% by weight of thecomposition.
 5. The composition of claim 1 wherein the combination ofmonomer and copolymer comprises about 20% to about 45% by weight of thecomposition.
 6. The composition of claim 1 wherein the filler comprisesfrom about 40% to about 80% by weight of the composition.
 7. Thecomposition of claim 1 wherein the filler is quartz, sand, glass oralumina trihydrate.
 8. The composition of claim 1 wherein thefree-radical catalyst is benzoyl peroxide.
 9. The composition of claim 1further comprising a thixotropic agent.
 10. The composition of claim 1further comprising a free-radical inhibitor.
 11. A low-temperaturecurable composition for anchoring materials in or to concrete or masonrythat is made by mixing a first composition which comprises:a. a solutionof methacrylate ester monomer and methacrylate ester/methacrylic acidcopolymer; b. from about 10% to about 90% of an inert, inorganic, solid,particulate filler; c. from about 0.1% to about 5% of a chain transferagent; and d. from about 0.01 to about 10% of an activator, anda secondcomposition which comprises from about 0.5% to about 10% of afree-radical catalyst, wherein said low-temperature curable compositionis curable at 20° F. (-7° C.) and wherein all percentages are by weightbased on the total weight of the curable composition.
 12. Thecomposition of claim 11 wherein the polymer to monomer ratio is in therange of about 1 to 9 to about 2.5 to 1 by weight.
 13. The compositionof claim 11 wherein the polymer to monomer ratio is in the range ofabout 1 to 4 to about 1 to 2.5 by weight.
 14. The composition of claim11 wherein the monomer/copolymer solution comprises about 20% to about90% by weight of the composition.
 15. The composition of claim 11wherein the monomer/copolymer solution comprises about 20% to about 45%by weight of the composition.
 16. The composition of claim 11 whereinthe filler comprises from about 40 to about 80by weight of thecomposition.
 17. The composition of claim 11 wherein the filler isquartz, sand, glass or alumina trihydrate.
 18. The composition of claim11 wherein the free-radical catalyst is benzoyl peroxide.
 19. Thecomposition of claim 11 further comprising a thixotropic agent.
 20. Thecomposition of claim 11 further comprising a free-radical inhibitor. 21.The composition of claim 11 wherein the second composition furthercomprises a filler.